MBExC Lecture

Prof. Dr. Jutta Engel from the Center for Integrative Physiology and Molecular Medicine (CIPMM) at the Saarland University will talk about “Ca²⁺ channel complexes in cochlear inner hair cells und further up the auditory pathway”.

Abstract
Voltage-gated Ca²⁺ channels (VGCC) are essential for chemical signal transmission in sensory cells and in neurons. In inner hair cells (IHC), sound-evoked receptor potentials open Ca_v1.3 Ca²⁺ channels that cause Ca²⁺ influx and exocytosis. However, VGCCs are not only crucial for synaptic transmission but also for developmental processes and for synaptic plasticity. Ten genes of pore-forming α₁ subunits as well as 4 genes of auxiliary β- and α₂δ subunits lead to a large functional variety of channel complexes.
I will focus on the composition and functions of IHC Ca_v1.3 channel complexes in development, in mature function and in the maintenance of the mature IHC phenotype. Further, I will report on the role of auxiliary α₂δ3 subunits of high voltage-activated Ca_v2.1 VGGCs for the ultrafast and precise synaptic transmission in spiral ganglion neurons, the auditory brainstem, and midbrain. α₂δ3 is encoded by Cacna2d3, which has been identified as risk gene for autism spectrum disorders in humans. Mice lacking Cacna2d3, which show impaired processing of amplitude-modulated tones at the level of the inferior colliculus and in behavior, present a model for an auditory processing disorder.

Host: Prof. Dr. Tobias Moser

Poster of the talk